tire pressure MERCEDES-BENZ SL550 2007 R230 User Guide

273 Operation
At the gas station
Coolant level
For information on checking the coolant
level, see “Coolant” (
page 280).
Engine oil level
For more information on checking the en-
gine oil level, see “Engine oil”
(
page 275).
Vehicle lighting
Check function and cleanliness. For more
information, see “Replacing bulbs”
(page 397).
Exterior lamp switch, see “Switching on
headlamps” (
page 55).
Tire inflation pressure
For information on checking the tire infla-
tion pressure, see “Checking tire inflation
pressure” (
page 292).

283 Operation
Tires and wheels
Tires and wheels
See an authorized Mercedes-Benz Center
for information on tested and
recommended rims and tires for summer
and winter operation. They can also offer
advice concerning tire service and
purchase.
Important guidelines

Only use sets of tires and rims of the
same type and make.


Tires must be of the correct size for the
rim.


Break in new tires for approximately
60 miles (100 km) at moderate
speeds.


Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire inflation pressure loss and
damage to the tire beads.


If vehicle is heavily loaded, check tire
inflation pressure and correct as
required.


Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1/8in (3 mm).


When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:

The wheel brakes or suspension
components can be damaged.


The operating clearance of the wheels
and the tires may no longer be correct.
Warning!
G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on re-
treads. The operating safety of the vehicle
cannot be assured when such tires are used.

284 OperationTires and wheelsTire care and maintenance
Regularly check your tire inflation pressure
at least once a month. For more informa-
tion on checking tire inflation pressure,
see “Recommended tire inflation pres-
sure” (
page 291).Tire inspection
Every time you check your tire inflation
pressure, you should also inspect your
tires for the following:


excessive treadwear (
page 285)


cord or fabric showing through the
tire’s rubber


bumps, bulges, cuts, cracks or splits in
the tread or side of the tire
Replace the tire if you find any of the above
conditions.
Make sure you also inspect the spare tire
periodically for condition and inflation.
Spare tires will age and become worn over
time even if never used, and thus should be
inspected and replaced when necessary.Life of tire
The service life of a tire is dependent upon
varying factors including but not limited to:


Driving style


Tire inflation pressure


Distance driven
Warning!
G
Regularly check the tires for damage. Dam-
aged tires can cause tire inflation pressure
loss. As a result, you could lose control of
your vehicle.
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
Warning!
G
Tires and spare tire should be replaced after
6 years, regardless of the remaining tread.

286 OperationTires and wheelsDirection of rotation
Unidirectional tires offer added advan-
tages, such as better hydroplaning perfor-
mance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the
intended direction of rotation (spinning) of
the tire.
Loading the vehicle
A label on your vehicle shows how much
weight it may properly carry.

The Tire and Loading Information
placard can be found on the driver’s
door B-pillar. This placard tells you im-
portant information about the number
of people that can be in the vehicle and
the total weight that can be carried in
the vehicle. It also contains information
on the proper size and recommended
tire inflation pressures for the original
equipment tires on your vehicle.


The Certification label, also found on
the driver’s door B-pillar tells you about
the gross weight capacity of your vehi-
cle, called the Gross Vehicle Weight
Rating (GVWR). The GVWR includes the
weight of the vehicle, all occupants,
fuel and cargo. The Certification label
also tells you about the front and rear
axle weight capacity, called the Gross
Axle Weight Rating (GAWR). The GAWR
is the total allowable weight that can be carried by a single axle (front or rear).
Never exceed the GVWR or GAWR for
either the front axle or rear axle.
1Driver’s door B-pillar
Following is a discussion on how to work
with the information contained on the
placard with regards to loading your vehi-
cle.
i
Spare wheels may be mounted against the
direction of rotation (spinning) even with a unidi-
rectional tire for temporary use only until the reg-
ular drive wheel has been repaired or replaced.
Always observe and follow applicable temporary
use restrictions and speed limitations indicated
on the spare wheel.

291 Operation
Tires and wheels
Recommended tire inflation pressure
Your vehicle is equipped with the Tire and
Loading Information placard located on
the driver’s door B-pillar (
page 286).The tire inflation pressure should be
checked regularly and should only be ad-
justed on cold tires. The tires can be con-
sidered cold if the vehicle has been parked
for at least 3 hours or driven less than
1 mile (1.6 km).
Follow recommended cold tire inflation
pressures listed on placard.
Keeping the tires properly inflated
provides the best handling, tread life and
riding comfort.
In addition to the tire placard on the
driver’s door B-pillar, also consult the fuel
filler flap for any additional information
pertaining to special driving situations. For
more information, see “Important notes on
tire inflation pressure” (
page 292).1Tire and Loading Information placard
with recommended cold tire inflation
pressures
The Tire and Loading Information placard
lists the recommended cold tire inflation
pressures for maximum loaded vehicle
weight. The tire inflation pressures listed
apply to the tires installed as original
equipment.
Warning!
G
Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.
i
Data shown on placard example are for illus-
tration purposes only. Tire data are specific to
each vehicle and may vary from data shown in
the illustration below. Refer to placard on vehicle
for actual data specific to your vehicle.

292 OperationTires and wheelsImportant notes on tire inflation
pressure
Tire temperature and tire inflation pressure
are also increased while driving, depending
on the driving speed and the tire load.
If you will be driving your vehicle at high
speeds of 100 mph (160km/h) or higher,
where it is legal and conditions allow,
consult the placard on the inside of the fuel
filler flap on how to adjust the cold tire in-
flation pressure. If you do not adjust the
tire inflation pressure, excessive heat can
build up and result in sudden tire failure.Be sure to readjust the tire inflation
pressure for normal driving speeds. You
should wait until the tires are cold before
adjusting the tire inflation pressure.
Some vehicles may have supplemental tire
pressure information for vehicle loads less
than the maximum loaded vehicle condi-
tion. If such information is provided, it can
be found on the placard located on the in-
side of the fuel filler flap.
Tire inflation pressure changes by approxi-
mately 1.5 psi (0.1 bar) per 18°F (10°C) of
air temperature change. Keep this in mind
when checking tire inflation pressure
where the temperature is different from
the outside temperature.
Checking tire inflation pressure
Regularly check your tire inflation pressure
at least once a month.
Check and adjust the tire inflation
pressure when the tires are cold. The tires
can be considered cold if the vehicle has
been parked for at least 3 hours or driven
less than 1 mile (1.6 km).
If you check the tire inflation pressure
when the tires are warm (the vehicle has
been driven for several miles or sitting less
than 3 hours), the reading will be
approximately 4 psi (0.3 bar) higher than
the cold reading. This is normal. Do not let
air out to match the specified cold tire in-
flation pressure. Otherwise, the tire will be
underinflated.
Warning!
G
If the tire inflation pressure repeatedly
drops:

Check the tires for punctures from
foreign objects.


Check to see whether air is leaking from
the valves or from around the rim.

293 Operation
Tires and wheels
Checking tire inflation pressure
manually
Follow the steps below to achieve correct
tire inflation pressure:
Remove the cap from the valve on one
tire.

Firmly press a tire gauge onto the
valve.

Read tire inflation pressure on tire
gauge and check against the recom-
mended tire inflation pressure on the
placard on the driver’s door B-pillar
(page 286). If necessary, add air to
achieve the recommended tire inflation
pressure.

Install the valve cap.

Repeat this procedure for each tire.Run Flat Indicator (Canada only)
While the vehicle is being driven, the Run
Flat Indicator monitors the set tire inflation
pressures by evaluating each wheel’s rota-
tional speed. This allows the system to de-
tect a significant loss of pressure in a tire.
If a wheel’s rotational speed changes due
to falling tire inflation pressure, you will
see a corresponding warning message in
the multifunction display.
The Run Flat Indicator may function in a re-
stricted manner or with a delay


if snow chains are mounted to the
vehicle


in presence of ice and snow


if you are driving on a loose surface
(e.g. sand or gravel)


if you are driving in a very sporty man-
ner (involving rapid acceleration or high
speeds in curves)
Warning!
G
Follow recommended tire inflation
pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly,
adversely affect handling and fuel economy,
and are more likely to fail from being over-
heated.
Do not overinflate tires. Overinflated tires
can adversely affect handling and ride
comfort, wear unevenly, increase stopping
distance, and result in sudden deflation
(blowout) because they are more likely to
become punctured or damaged by road
debris, potholes etc.
Do not overload the tires by exceeding the
specified load limit or vehicle capacity
weight as indicated on the placard on the
driver’s door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.
i
If you have overfilled the tire, release tire in-
flation pressure by pushing the metal stem of the
valve with e.g. a tip of a pen. Then recheck the
tire inflation pressure with the tire gauge.

294 OperationTires and wheels
Reactivating the Run Flat Indicator
The tire inflation pressure monitor must be
reactivated in the following situations:

if you have changed the tire inflation
pressure


if you have replaced the wheels or tires


if you have installed new wheels or
tires

Using the tire placard on the driver’s
door B-pillar or, if available, the inside
of the fuel filler flap, make sure the tire
inflation pressure of all four tires is cor-
rect.
Warning!
G
When the multifunction display shows the
message
Tire pressure Check tires
,
one or more of your tires is significantly un-
der-inflated. You should stop and check
your tires as soon as possible, and inflate
them to the proper tire inflation pressure as
indicated on the vehicle’s tire information
placard. Driving on a significantly under-in-
flated tire causes the tire to overheat and
can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life,
and may affect the vehicle’s handling and
stopping ability. Each tire, including the
spare, should be checked monthly when
cold and set to the recommended tire infla-
tion pressure as specified on the Tire And
Loading Information placard (
page 287)
or on the tire inflation pressure label
(
page 291).
Warning!
G
The Run Flat Indicator does not provide a
warning for wrongly selected tire inflation
pressures. Always adjust tire inflation pres-
sure according to the placard on the driver’s
door B-pillar or fuel filler flap.
The Run Flat Indicator does not replace reg-
ular checks of the tire inflation pressures
since a gradual pressure loss in all four tires
cannot be detected by the Run Flat
Indicator.
The Run Flat Indicator is not able to issue a
warning due to a sudden dramatic loss of
tire inflation pressure (e.g. tire blowout
caused by a foreign object). In this case
bring the vehicle to a halt by carefully apply-
ing the brakes and avoiding abrupt steering
maneuvers.
Warning!
G
The Run Flat Indicator can only warn you in
a reliable manner if you have set the correct
tire inflation pressures for each tire.
If an incorrect tire inflation pressure was
set, the system will monitor the pressure ac-
cording to the incorrect value.

295 Operation
Tires and wheels

Switch on the ignition (
page 39).
Make sure the standard display menu
appears in the multifunction display
(
page 145).

Press buttonk orj repeatedly
until the following message appears in
the multifunction display:Run Flat Indicator
active
Menu: R-Button

Press the reset button (
page 27).
The following message will appear in
the multifunction display:
Restart
Run Flat Indicator?
If you wish to confirm activation:
Press buttonæ.
The following message will appear in
the multifunction display:Run Flat Indicator
restarted
After a certain “learning phase”, the Run
Flat Indicator checks the set pressure val-
ues for all four tires.
If you wish to cancel activation:
Press buttonç.Checking tire pressure electronically
with the Tire Pressure Monitoring
System (TPMS), (USA only)
i
The T
ire P
ressure M
onitoring S
ystem
(TPMS) is equipped with a combination low tire
pressure/TPMS malfunction telltale in the in-
strument cluster (
page 29). Depending on
how the telltale illuminates, it indicates a low tire
pressure condition or a malfunction in the TPMS
system itself:


If the telltale illuminates continuously, one
or more of your tires is significantly under-in-
flated. There is no malfunction in the TPMS.


If the telltale flashes for 60 seconds and
then stays illuminated, the TPMS system it-
self is not operating properly.

296 OperationTires and wheelsThe TPMS only functions on wheels that
are equipped with the proper electronic
sensors. It monitors the tire inflation pres-
sure, as selected by the driver, in all four
tires. A warning is issued to alert you to a
decrease in pressure in one or more of the
tires.Warning!
G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the placard on the driver’s door B-pillar or, if
available, the supplemental tire pressure in-
formation on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by care-
fully applying the brakes and avoiding
abrupt steering maneuvers.
Warning!
G
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or the tire inflation pressure
label. If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or the tire inflation pressure label,
you should determine the proper tire infla-
tion pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a significant-
ly underinflated tire causes the tire to over-
heat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping ability. Please
note that the TPMS is not a substitute for
proper tire maintenance, and it is the driv-
er’s responsibility to maintain correct tire
pressure, even if under-inflation has not
reached the level to trigger illumination of
the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined with the low tire pressure telltale.
When the system detects a malfunction, the
telltale will flash for approximately
one minute and then remain continuously
illuminated. This sequence will continue
upon subsequent vehicle start-ups as long
as the malfunction exists. When the mal-
function indicator is illuminated, the system
may not be able to detect or signal low tire
pressure as intended.